Zoran Mijuskovic

Immune Complexes and Complement in Serum and Synovial Fluid of Rheumatoid Arthritis Patients

Immune Complexes and Complement in Serum and Synovial Fluid of Rheumatoid Arthritis Patients Rheumatoid arthritis (RA) is predominantly an intraarticular inflammatory and autoimmune disease that involves different autoantibodies and effector mechanisms. The aim of the study was to determine the utility of Circulating Immune Complexes (CIC) and complement components (C3c, C4) as possible markers for the disease activity in laboratory diagnostics. In a cross-section study 59 patients, according to the clinical criteria, were categorized into two groups: group with moderate (MA, n=24), and group with severe activity (SA, n=35) of RA. The concentration of CIC, C3c and C4 in sera (S) and synovial fluids (SF) was examined by an immunonephelometric method in both groups and compared with values in the control group (n=15) of patients with lesions of the menisci. Obtained results showed that there was no statistical significance in the values of C3c and C4, in both biological fluids, among all tested groups. Significant differences were found in the levels of CIC in both fluids, while testing the parameters (× ± SD, IU/mL) in the sera of groups with SA and MA of RA: 7.43 ± 13.40; 3.01 ± 2.92 (p<0.05) and SF: 13.47 ± 21.1, 5.33 ± 7.53 (p<0.001), respectively. These differences were higher between the group with SA and CG. Results for the concentrations of CIC were significantly higher in SF compared to sera: in the RA group with SA by 77% and group with MA by about 82%. These data could provide a confirmation of the hypothesis about local, intraarticular autoantibodies and subsequent CIC production. It can be concluded that the examination of CIC concentration in serum, and where it is possible in SF, is a useful marker of disease activity in RA patients, in contrast to the tested components of the complement. This statement does not exclude their consumption within immune effector mechanisms, but elicits the possibility that lower molecular fragments (C3d, C4d), as well as the novel activation products, could be better disease activity markers in RA patients. Imunski Kompleksi i Komplement u Serumu i Sinovijalnoj Tečnosti Kod Bolesnika sa Reumatoidnim Artritisom Reumatoidni artritis (RA) jeste predominantno intraartikularna zapaljenska i autoimunska bolest u koju su uključena različita autoantitela i efektorni mehanizmi. Cilj ispitivanja je bio da se ustanovi značaj cirkulišućih imunskih kompleksa (CIK) i komponenti komplementa (C3c, C4), kao pokazatelja stepena aktivnosti RA za laboratorijsku dijagnostiku. U studiji preseka stanja je ispitano 59 bolesnika koji su prema kliničkim kriterijumima za aktivnost RA podeljeni u dve grupe: grupu sa umerenom (UA, n=24) i grupu sa visokom aktivnošću (VA, n=35) RA. Koncentracije CIK, C3c i C4 u serumu i sinovijalnoj tečnosti (ST) određivane su imunonefelometrijskom metodom u obe grupe ispitanika i upoređene sa vrednostima u kontrolnoj grupi od 15 pacijenata s povredama meniskusa. Rezultati su pokazali da nije bilo statistički značajnih razlika u koncentracijama za C3c i C4 u oba biološka uzorka između ispitivanih grupa. Statistički značajne razlike u koncentracijama CIK utvrđene testiranjem vrednosti (× ± SD, IU/mL) u serumu između grupe sa VA i grupe sa UA RA bile su: 7,43 ± 13,40; 3,01 ± 2,92 (p < 0,05) i za vrednosti u ST: 13,47 ± 21,1, 5,33 ± 7,53 (p < 0,001). Razlike su bile više izražene između grupe sa VA RA i KG. Rezultati koncentracija CIK su bili značajno viši u ST u odnosu na serum u obe grupe bolesnika: u grupi sa UA za 77% a u grupi sa VA RA za 82%. Ti podaci idu u prilog potvrdi hipoteze o lokalnoj, intraartikularnoj produkciji autoantitela, odnosno CIK. Može se zaključiti da je laboratorijsko određivanje koncentracije CIK korisan pokazatelj stepena aktivnosti RA, što se ne odnosi na ispitivane komponente komplementa. To ne isključuje njihovu aktivnost u okviru efektornog imunskog mehanizma, ali ukazuje na to da bi manji molekulski fragmenti (C3d, C4d) i novi aktivacioni produkti mogli biti bolji pokazatelji stepena aktivnosti RA.

Urinary Cystatin C as a Marker of Tubular Dysfunction

Urinary Cystatin C as a Marker of Tubular Dysfunction Cystatin C (CysC) is a nonglycosylated 13 KD protein that belongs to the type II cystatin gene family. It is a strong inhibitor of cysteine proteinases, freely filtered by the kidney glomerulus and reabsorbed by the tubulus, where it is almost totally catabolized. Remainder of the nonmetabolized CysC is eliminated in urine and may represent a useful marker of tubular dysfunction. The aim of the study was to confirm the clinical importance of the quantitative determination of CysC by an automated immunonephelometric method (DADE Behring). Two groups of patients were examined: one with glomerular (GD, n=36) and one with tubular dysfunction (TD, n=31), and compared with the control group (CG, n=31) of healthy males and females from laboratory personnel (n=11) and patients on routine systematic examination (n=20), from 25 to 58 years old. The patient groups were categorised according to the urine analysis of total proteins, creatinine and adequate proteins electrophoretic panel. CysC concentration in CG was in the range of 0.02-0.15 mg/L; 0.01-0.48 mg/L and 0.25-18 mg/L in GD and TD groups respectively. Values of means ± SD for patient groups (GD=0.11 ± 0.14; TD=3.92 ± 3.75 mg/L) showed statistical significance (p<0.001) in the TD group in relation to GD and CG groups. It confirms that quantitative determination of CysC in one urine portion, with a fast laboratory method, might be a useful marker of tubular dysfunction, especially in emergency situations, taking into account that there is no interference of circadian variation on its concentration. Cistatin C U Urinu Kao Pokazatelj Tubulskog Oštećenja Cistatin C (CysC) je neglikozirajući protein molekulske mase od 13 KD koji pripada tipu II genske familije cistatina. Ima funkciju inhibitora cistein proteinaze koji se potpuno filtrira u glomerulima a zatim reapsorbuje i kataboliše u proksimalnim tubulima. Preostali i nerazgrađen CysC biva eliminisan urinom pa zato može da bude koristan marker tubulskih oštećenja. Cilj ispitivanja bio je da se utvrdi klinički značaj kvantitativnog određivanja CysC automatizovanom imunonefelometrijskom metodom (DADE Behring). Ispitane su dve grupe bolesnika: sa tubulskom (TI) i glomerulskom (GI) insuficijencijom, i upoređene sa kontrolnom grupom (KG) koju su činile zdrave osobe oba pola (n=31), laboratorijski personal (n=11) i pacijenti na sistematskom pregledu (n = 20), starosne dobi od 25 do 58 godina. Kategorizacija grupa sa GI (n=36) i TI (n=31) ustanovljena je na osnovu koncentracije ukupnih proteina, kreatinina i adekvatnih elektroforetskih denzitometrijskih varijanti karakterističnih za obe grupe. Koncentracija CysC u KG bila je u opsegu 0,02-0,15 mg/L, u grupi sa GI 0,01-0,48 mg/L, a u grupi sa TI 0,25-18 mg/L. Rezultati vrednosti (medijana±SD) za grupu sa GI (0,11 ± 0,14 mg/L) i grupu sa TI (3,92 ± 3,75 mg/L) pokazali su statistički značajnu razliku (p< 0,0001) između grupe sa TI i grupa sa GI i KG. Pokazano je da određivanje CysC u jednom uzorku urina brzim laboratorijskim postupkom može biti koristan test za diferencijalnu dijagnostiku tubulskih u odnosu na glomerulska oštećenja, posebno u urgentnim stanjima, s obzirom na činjenicu da na njegovu koncentraciju nema uticaja cirkadijalnih ritmova.

Multiple myeloma invasion of the central nervous system

INTRODUCTION Multiple myeloma (MM) is characterized by the presence of neoplastic proliferating plasma cells. The tumor is generally restricted to the bone marrow. The most common complications include renal insufficiency, hypercalcemia, anemia and reccurent infections. The spectrum of MM neurological complications is diverse, however, involvement of MM in the cerebrospinal fluid (CSF) and leptomeningeal infiltration are rare considered. In about 1% of the cases, the disease affects the central nervous system (CNS) and presents itself in the form of localized intraparenchymal lesions, solitary cerebral plasmocytoma or CNS myelomatosis (LMM). CASE REPORT We presented the clinical course of a 55-year-old man with MM and LMM proven by malignant plasma cells in the CSF, hospitalized with the pain in the thoracic spine. His medical history was uneventful. There had been no evidence of mental or neurological impairment prior to the seizures. Physical examination showed no abnormalities. After a complete staging, the diagnosis of MM type biclonal gammopathia IgG lambda and free lambda light chains in the stage III was confirmed. The treatment started with systemic chemotherapy (with vincristine, doxorubicin plus high-dose dexamethasone--VAD protocol), radiotherapy and bisphosphonate. The patient developed weakness, nausea, febrility, dispnea, bilateral bronchopneumonia, acute renal insufficiency, confusions, headaches and soon thereafter sensomotor aphasias and right hemiparesis. The patient was treated with the adequate therapy including one hemodyalisis. His neurological status was deteriorated, so Multislice Computed Tomography (MSCT) of the head was performed and the findings were normal. Analysis of CSF showed pleocytosis, 26 elements/mL and increased concentrations of proteins. Cytological analysis revealed an increased number of plasma cells (29%). Electrophoretic analysis of proteins disclosed the existance of monoclonal components in the serum, urine and CSF. Immunofixation electrophoretic and quantitative nephelometric tests confirmed Biclonal multiple myeloma of IgG lambda and light chain lambda isotypes. Analysis of neurothropic viruses with ELISA methods was negative. Once the presence of LMM was confirmed, the patient received intrathecal chemotherapy with methotrexate, cytosine arabinoside, dexamethasone three times a week, and systemic high doses of dexamethasone iv like a single agent without craniospinale irradiations. Despite the treatment, the patient died one month after the diagnosis. Autopsy was not performed. CONCLUSION Presented patient, as well as most other patients with MM progressing to CN Sinfiltration was in the stage III. In addition to the detailed clinical examination, and all investigations required for MM diagnosis and staging of the disease, we introduced the additional CSF examination and calculation of kappa lambda ratio, that helped us make an early diagnosis and prognosis of MM with LMM. Although LMM had a low prevalence, it could be more frequent than expected especially in patients with high risk. CSF examination with positive plasma cells and abnormal morphology remains the hallmark for diag nosing CNS infiltration.

Free Light Chains of Immunoglobulin as a Prognostic Factor for Some Plasmaproliferative Diseases

Free Light Chains of Immunoglobulin as a Prognostic Factor for Some Plasmaproliferative Diseases Quantitation of monoclonal immunoglobulins and their fragments is used for monitoring the plasmaproliferative disease course and the effect of therapy. The aim of free light chains examination was to evaluate the significance of the FLC ratio as a prognostic factor for remission, progression and survival in different disease groups. The concentrations of immunoglobulins and free light chains were measured by an immunonephelometric method on a »SIEMENS« DADE BN II analyser with reagents (Freelite, The Binding Site, UK). In this examination 151 patients from 3 different disease groups: 1. Light chain disease or Bence Jones myeloma (37), 2. Biclonal gammopathy with FLC (23) and 3. Monoclonal gammopathy of undetermined significance (91), were investigated during a period of 7 years. The reference interval for FLC ratio is 0.26-1.65. According to the International Staging System for multiple myeloma, a serum FLC ratio of <0.03 or >32 was taken as abnormal. The patients with light chain disease and biclonal gammopathy with FLC with an abnormal FLC ratio and a combination of adverse risk factors (76.7%) had median survival times of 22-30 months, versus patients with a normal or slightly varied FLC ratio without adverse risk factors (23.3%) with median survival times of 39-51 months. About 38% of patients who had shown lowered free light chains values by more than 50% under therapy, achieved disease remission in the light chain disease and biclonal gammopathy with FLC groups. In the group of patients with monoclonal gammopathy of undetermined significance, 66.0% had a normal or slightly modified FLC ratio which corresponds to low and low-intermediate risk of disease progression, as opposed to 34.0% with an abnormal FLC ratio (<0.25 or >4) which corresponds to high and high-intermediate risk. An abnormal FLC ratio in the examined groups could be an independent risk factor for progression and poorer disease prognosis. Slobodni Laki Lanci Imunoglobulina Kao Prognostički Faktor Kod Nekih Plazmaproliferativnih Bolesti Kvantitativno određivanje monoklonskih imunoglobulina i njihovih fragmenata koristi se za praćenje toka i terapijskog odgovora kod plazmaproliferativnih bolesti. Cilj određivanja slobodnih lakih lanaca imunoglobulina u serumu bolesnika jeste provera značaja njihovog količnika (κ/λ indeks) kao prognostičkog faktora remisije, progresije i preživljavanja. Koncentracije imunoglobulina i slobodnih lakih lanaca određivane su imunonefelometrijskom metodom na analizatoru SIEMENS DADE Behring II sa reagensima (FREELITE, The Binding Site, UK). U ispitivanje je uključen 151 bolesnik tokom perioda od 7 godina, koji su razvrstani u 3 grupe: 1. bolest lakih lanaca ili Bence Jones mijelom (37); 2. biklonalna gamapatija sa slobodnim lakim lancima (23) i 3. monoklonska gamapatija neutvrđenog značaja (91). Referentnim intervalom za κ/λ indeks smatraju se vrednosti 0,26-1,65. Prema Internacionalnom prognoznom indeksu za multipli mijelom, kao patološki uzet je κ/λ indeks <0,03 ili >32. Bolesnici iz prve dve grupe sa patološkim k/λ indeksom i kombinacijom nepovoljnih faktora rizika (76,7%) imali su prosečno vreme preživljavanja 22-30 meseci, nasuprot bolesnicima sa fiziološkim ili neznatno izmenjenim κ/λ indeksom bez nepovoljnih faktora rizika (23,3%), sa prosečnim vremenom preživljavanja 39-51 mesec. Oko 38% bolesnika koji su pod terapijom imali sniženje κ/λ indeksa >50% su ostvarili remisiju bolesti. U grupi ispitanika sa MGNZ, 66,0% je imalo fiziološke ili neznatno izmenjene κ/λ indekse, što odgovara niskom i srednje niskom riziku progresije, nasuprot 34,0% sa patološkim κ/λ indeksom (<0,25 ili >4), što odgovara srednje visokom i visokom riziku progresije. Postojanje patološki značajnog κ/λ indeksa u ispitivanim grupama predstavlja nezavisan faktor rizika za progresiju bolesti i lošiju prognozu.

Arthrosonography and the Biomarker Cartilage Oligomeric Matrix Protein in the Detection of Knee Osteoarthrosis Effusion

Arthrosonography and the Biomarker Cartilage Oligomeric Matrix Protein in the Detection of Knee Osteoarthrosis Effusion Osteoarthrosis of the knee is a degenerative disease with inflammatory episodes objectively shown by arthrosonography. Cartilage Oligomeric Matrix Protein - COMP is a useful biomarker for early cartilage destruction. The aim of this paper is a comparative analysis of the clinical, arthrosonographic findings and the COMP concentration in the sera of patients for the detection of joint inflammation. The analysis included 88 patients with knee OA. Clinical examination determined the outflow, arthrosonography the size of synovitis and effusion, and serum analysis the COMP concentration (ng/ml). Minimum outflow had 34.1% of patients, moderate 22.7%, and significant 4.5%. Sensitivity of the clinical diagnosis of outflow is 73%, and specificity 73% (p=0.000). Seventy five percent of patients had effusion; 28.4% of patients in the suprapatellar recessus (SR), 27.3% in the medial (MR), and 62.5% in the lateral (LR). In SR, effusion was 10.13±4.35 mm, MR 8.53±2.27 mm, LR 11.38±4.44 mm. Synovitis was found in 67% of patients, in SR the size of 4.84±3.57 mm, in MR 3.15±1.86 mm, in LR 6.09±2.80 mm. The average value of the size of effusion in patients with significant outflow in SR was 13.85 (10.36-17.43) mm (p=0.000), MR 4.9 (0-10.22) mm (p=0.008), LR 12.0 (11.34-14.50) mm (p=0.000), in LR with moderate outflow 6.94 (1.16-8.13) mm and minimum outflow 4.9 (0-7.25) mm. There is a significant correlation between the size of synovitis and effusion in the SR, MR and LR (p=0.000). The average value of the concentration of COMP in patients without effusion was 54 (44.5-58) ng/ml, with effusion 57 (48.75-64.25) ng/ml (p=0.030). Arthrosonography and the determination of the COMP concentration are sensitive methods for diagnosing joint effusion. Artrosonografija I Biomarker Oligomerni Protein Matriksa Hrskavice U Detekciji Efuzije Kod Osteoartroze Kolena Osteoartroza (OA) kolena je degenerativna bolest sa inflamatornim epizodama koje artrosonografija objektivno prikazuje. Oligomerni protein matriksa hrskavice - COMP je korisan marker za ranu destrukciju hrskavice. Cilj rada je uporedna analiza kliničkog, artrosonografskog pregleda i koncentracije COMP u serumu bolesnika radi detekcije zglobne inflamacije. Analizom je obuhvaćeno 88 bolesnika sa OA kolena. Kliničkim pregledom je utvrđen izliv, artrosonografskim veličina sinovitisa i efuzije, analizom seruma koncentracija COMP (ng/ml). Minimalan izliv je imalo 34,1% bolesnika, umeren 22,7%, značajan 4,5%. Senzitivnost kliničke dijagnoze izliva je 73%, a specifičnost 73% (p=0,000). Efuziju je imalo 75% bolesnika, u suprapatelarnom recesusu (SR) efuziju je imalo 28,4% bolesnika, medijalnom (MR) 27,3%, lateralnom (LR) 62,5%. U SR efuzija je bila 10,13±4,35 mm, MR 8,53±2,27 mm, LR 11,38±4,44 mm. Sinovitis je nađen kod 67% bolesnika, u SR veličine 4,84±3,57 mm, MR 3,15±1,86 mm, LR 6,09±2,80 mm. Srednja vrednost veličine efuzije kod bolesnika sa značajnim izlivom u SR je bila 13,85 (10,36-17,43) mm (p=0,000), MR 4,9 (0-10,22) mm (p=0,008), LR 12,0 (11,34-14,50) mm (p=0,000), samo u LR sa umerenim izlivom 6,94 (1,16-8,13) mm i minimalnim izlivom 4,9 (0-7,25) mm. Postoji značajna povezanost veličine sinovitisa i efuzije u SR, MR i LR (p=0,000). Srednja vrednost koncentracije COMP kod bolesnika bez efuzije je bila 54 (44,5-58) ng/mL, sa efuzijom 57 (48,75-64,25) ng/mL (p=0,030). Artrosonografija i određivanje koncentracija COMP predstavljaju senzitivne metode u dijagnostikovanju zglobne efuzije.

Comparison of Two Commercial Cyclosporin Assays

Comparison of Two Commercial Cyclosporin Assays A new Dade Behring Cyclosporin A (CsA) assay has been made commercially accessible recently. The aim of this study was to examine the analytical performance of this assay and the correlation with the Abbott Diagnostics assay. The accuracy and precision within-run were good, but precision between-run slightly exceeded the manufacturers recommendation on one quality-control material. Dade Behring CsA whole blood results from the kidney recipients (n = 104) were lower (p<0.001) than the Abbott results. The correlation between these two assays was significant (y = -15.61 + 0.751x; r= 0.974; p<0.001). Dade Behring CsA assay demonstrates adequate performance characteristics for routine clinical use and the main advantage is the full automatization without the need for samples pretreatment. Poredenje Dva Komercijalna Testa Za Odredivanje Ciklosporina A Odnedavno je komercijalno dostupan novi Dade Behring test za odredivanje CsA u krvi. Naš cilj bio je da ispitamo analitičke karakteristike ovog testa i korelaciju sa Abbott Diagnostics testom. Tačnost i preciznost u seriji Dade Behring testa bili su zadovoljavajući, dok je preciznost iz dana u dan blago prevazilazila preporuku proizvodača u jednoj kontroli. Odredivanjem CsA u krvi pacijenata kojima je izvršena transplantacija bubrega (n=104) Dade Behring testom, dobijene su niže vrednosti (p<0,001) nego Abbott testom. Korelacija ove dve metode bila je statistički značajna (y = -15,61 + 0,751x; r = 0,974; p<0,001). Dade Behring test za odredivanje CsA pokazuje odgovarajuće karakteristike za rutinsku kliničku upotrebu, a glavna prednost je potpuna automatizacija testa bez potrebe za prethodnom pripremom uzorka.

Kidney failure as an unusual initial presentation of biclonal gammopathy (IgD multiple myeloma associated with light chain disease)--a case report.

INTRODUCTION Immunoglobulin D (IgD) myeloma is a rare disease, about 2% of all myelomas, even rarer when accompanied with another multiple myeloma in biclonal gammopathy. We presented a case of biclonal gammopathy-as-sociated manifestation of IgD myeloma and light chain disease in a patient who initially had renal failure. CASE REPORT 37-year-old male approximately one month before hospitalization began to feel malaise and fatigue along with decreased urination. Laboratory analysis revealed azotemia. A dialysis catheter was placed and hemodialysis started. The patient was then admitted to our hospital for further tests and during admission, objective examination revealed pronounced paleness with hepatosplenomegaly and hypertension (170/95 mmHg). Laboratory analysis showed erythrocyte sedimentation rate 122 mm/h, expressed anemic syndrome (Hb 71 g/L) and renal failure dialysis rank: creatinine 1,408 micromol/L, urea 31.7 mmol/L. There was two M components in serum protein electrophoresis: IgD lambda and free light chain lambda. Proteinuria was nephrotic rank (5.4 g/24 h), whose electrophoresis revealed 2 M components--massive in alpha 2 fraction of 71%; 7% in the discrete beta fraction, beta 2M / serum 110 mg / L, in urine 1.8 mg/L--extremely high; IgL kappa I lambda index 1:13 (reference value ratio 2:1). The findings pointed to double myeloma disease: IgD myeloma and Bence Jones lambda myeloma. Bone biopsy confirmed IgD myeloma lambda 100% infiltration medulla predominantly plasmablasts. The treatment continued with hemodialysis 3 times per week with chemotherapy protocol bortezomib, doxorubicin, dexamethasone. After 4 cycles of chemotherapy, there was a decrease of IgD, lamda-light chains, reduction in proteinuria (1.03 g/24 h), so hemodialysis was reduced to once per week. Six months after treatment initiation the patient underwent autologous bone marrow transplantation. In a 2-year follow-up period double myeloma disease showed complete remission. CONCLUSION The presented rare form of double myeloma disease with initial renal insufficiency underscores the importance of careful observation and teamwork that can alter the course of this serious disease.

Biomarkers and Ultrasound in the Knee Osteoarthrosis Diagnosis

This study will present contemporary methods of the knee osteoarthrosis (OA) diagnosis – arthrosonography and biomarkers, which are applied and recommended in the modern practice. Advantages of ultrasound diagnostics (arthrosonography) and serum biomarkers in rheumatologic diagnostics will be documented through this research which applied these methods. Ultrasound has become an integral part of clinical practice and is applied in many fields of medicine, however, in rheumatology it has not been fully recognized yet. Appliance of biomarkers in knee osteoarthrosis diagnosis is considerably a more expensive method, and has not been usually used for this purpose. It is very precise though in detection of changes in knee joint with osteoarthrosis. The goal of this study is to affirm the ultrasound diagnostic method for many advantages it has comparing to other methods which have been used as routine, and to recommend it as a important part of clinical rheumatologic checkup. The following methods are usually used for visualisation of knee joint: radiography, nuclear magnet resonance, computerised tomography, arthroscopy and arthrography. The most commonly applied and routine diagnostic method is radiography. However, the conventional radiography and computerised tomography are the methods without possibility of direct visualisation of the joint cartilage. Narrowing of the joint area is only an indirect indication of a joint damage, and early changes on the cartilage cannot be evaluated (Batalov et al.,2000). Nuclear magnetic resonance provides direct information on changes in different joint tissues, which is why it is nowadays appropriate for the knee osteoarthrosis diagnosis. However, its appliance is limited due to the very expensive medical examination. Methods of direct visualisation of the joint cartilage are arthrography and arthroscopy, which are less used in clinical practice, due to their invasiveness and limited indications.

Evaluation of Platelet Activation Parameters as Quality Markers for the Stored Platelets

Evaluation of Platelet Activation Parameters as Quality Markers for the Stored Platelets In order to investigate the potential use of platelets activation parameters as routine quality control indicators during liquid storage, 27 PC-BC units were kept at 22 °C for up to 5 days. Routine parameters, including a platelet count, mean platelet volume and the parameters of activity: mean platelet component concentration, platelet component distribution width, mean platelet mass, platelet mass distribution width and number of platelet clumps were measured on the Bayer ADVIA 120 hematology analyzer. The platelet surface antigen CD62P was investigated using monoclonal antibodies on the flow cytometer Coulter-Epics XL and the platelet factor 4 and β-thromboglobuline, the main components of the α-granules, were also measured. The reduction in MPV, MPC, PCDW and MPM and the simultaneous increase in PF4, β-TG and CD62P expression reflected the PLT degranulation and activation. Minimizing cell damage during collection and storage is imperative for obtaining the PLT adequate in number and viability. Procena Parametara Trombocitne Aktivacije Kao Kvalitativnih Markera Za Skladištene Trombocite U cilju ispitivanja mogućnosti upotrebe aktivacionih parametara trombocita kao indikatora i markera njihovog kvaliteta, ispitali smo 27 jedinica koncentrovanih trombocita izdvojenih procesiranjem iz jedinica cele krvi, «buffy coat-a» (KC-BC), skladištenih 5 dana na temperaturi 20±2 °C. Ispitivani su rutinski parametri, koji uključuju ukupni broj trombocita i srednji volumen trombocita, kao i parametri aktivacije trombocita: srednja koncentracija komponenti trombocita, distribucija širine komponenti trombocita, srednja masa trombocita, distribucija širine mase trombocita i broj trombocitnih klampova, na Bayer ADVIA 120 hematološkom analizatoru. Trombocitni površinski antigen CD62P ispitivan je anti-CD62P monoklonskim antitelom na «flow» citometru Coulter-Epics XL, a takođe su ispitani PF4 i β-TG kao glavne sekretorne komponente α-granula. Redukcija u MPV, MPC, PCDW i MPM, uz simultano povećanje koncentracije PF4, β-TG i ekspresije CD62P, ukazuje na degranulaciju i aktivaciju trombocita. To ukazuje na neophodnost minimiziranja ćelijskog oštećenja tokom sakupljanja i skladištenja uzoraka kao na imperativ za dobijanje trombocita adekvatnog broja i vijabilnosti.